Development of Pillared Clays for Wet Hydrogen Peroxide Oxidation of Phenol and Its Application in the Posttreatment of Coffee Wastewater

Table 3

Some examples of WPHCO of water pollutants (model molecules) or real effluents, using a Fenton reaction catalyzed by pillared clays.

Clay catalyst	Organic pollutant	Performances reached	Reference
Al/Fe-PILC	Treatment of municipal leachate from landfill by catalytic wet peroxide oxidation using an Al/Fe-pillared montmorillonite	𝑇 = 18 ± 2°C; 𝑋COD = 50%; This advanced oxidation process has; enhanced the biodegradability index of the leachate from 0.135 to 0.321 in 4 h	[43]
Cu-PILC; Fe-PILC	Phenolic compounds (p-coumaric and p-hydroxybenzoic acids) and real olive oil milling wastewater (OMW)	𝑇=70 °C; 𝑋p-coumaricacid=100%,; 𝑋p-hydroxybenzoicacid = 100%, 𝑋TOC: 74–80%; Olive oil milling wastewater; 𝑋polyphenols = 46–48%, 𝑋TOC: 18–22%	[69]
Cu/Al-PILC	Tyrosol, major compound of the polyphenolic fraction present in olive oil mill wastewaters	𝑇 = 25–80°C; 𝑋Tyrosol = 100%, 𝑋TOC ∼ 80%; Without significant leaching of copper ions	[70]
(Al-Fe)PILC	Polyphenols in olive mill wastewater (OMW)	𝑇 = 25–70°C; 𝑋COD = 37–69%, 𝑋polyphenols = 54–100%; Pretreated OMW reduced considerably the COD and total phenolic contents	[71]
Cu-PILC	Real wastewaters from agro-food production (Citrus juice production and olive oil milling wastewater)	Citrus juice production wastewater; 𝑇 = 80°C, 𝑋polyphenols = 65–98%; 𝑋TOC = 20–52%; Cu leaching = 0.21–0.64 ppm; Olive oil milling wastewater; 𝑇 = 80°C, 𝑋polyphenols = 18–39%,; 𝑋TOC = 7–30%	[72]
Cu-AZA	Wet hydrogen peroxide catalytic oxidation of olive oil mill wastewaters using a Cu-pillared clay catalyst	𝑇 = 80°C; 𝑋polyphenols = 45%, 𝑋TOC = 13.5%; No copper leaching during the oxidation reactions	[73]